Toynbee's A Study of History
Arnold J. Toynbee's 1952 analysis of the genesis, growth, breakdown and disintegration of civilizations is a mammoth work spanning 10 volumes . The motivation for such an effort was the realization that, of the 21-23 major civilizations he identifies, all but a few are dead. This review was written after reading the two-volume abridgement by D. C. Somervell .
Any patterns to be found in human history are surely caused by the unfortunate consistencies of our fallen nature. However, it is also true that people are quite proficient at seeing patterns where none exist. Although I initially viewed Toynbee with some skepticism, I discovered that he has an excellent grasp of human nature, and molds his patterns solidly around this foundation.
First, I present a (necessarily) brief review of Toynbee's principal ideas, followed by a look at the degree to which our nation may align with Toynbee's pattern of the rise and fall of civilizations.
Toynbee saw civilizations as primarily composed of two groups of people. (This is of course a generalization--people are never so clearly delineable, but one must occasionally simplify to make a point.) The creative minority is the class that leads a civilization. This group originates useful ideas, solves problems, and serves as the template to be copied by the uncreative majority. The ideas of the leaders are copied by mimesis, or the relatively blind imitation of behavior. 
During the growth phase of a civilization, mimesis is a positive force, as it allows the purposes, motivations and visions of the leadership to be effectively followed by the rest. In fact, new civilizations grow numerically and geographically by offering a powerful vision that draws in the relatively less civilized surrounding peoples. These visions and motivations are what energize the culture to grow.
Challenges are a natural part of the life of any civilization. Such challenges may be military, social, or environmental; they may come from within or without. A society in its growth phase will respond to its challenges in an effective manner, which strengthens the people for the next challenge. However, it appears that success is its own undoing. As with individuals and corporations, once a nation is caught up in the momentum produced by success, it becomes increasingly difficult to adapt as new challenges require it. More energy is needed merely to maintain what one has.
Whatever the particular cause, at some point in all civilizations, a challenge arises with which the leadership, and hence the people, cannot deal in a positive way. Rather than collapsing, the now-declining civilization forms a universal state. This move does not represent the zenith of a civilization as some historians argue, but actually represents a last-ditch effort to preserve the status quo. At this point, the following things take place: The creative minority, which has failed to answer the latest challenge, ceases to lead by positive example. Rather than cede their position at the top of society, they choose to become a dominant minority, leading by force. The people withdraw their active allegiance from the leadership, retaining at most a tendency to mimic its bad characteristics. There is a loss of social unity, further weakening the society. The cultures on the outside see this negative transformation, and turn against the civilization.
The civilization's doom is sealed by a confluence of the following factors: The "barbarians" on the outside can nip indefinitely at the heels of the civilization, yet are able to retreat easily when counter-attacked. Being less civilized, they have less to lose when handed a temporary defeat. They learn economic and military strategies from the dying civilization, which they can employ in competition with it. Even entropy is on the side of the barbarians, as it is always easier to destroy life, liberty and property than it is to create them. Inside the universal state, the condition of "peace" (now under oppression) lulls the people into a false sense of security, sometimes even resulting in an anti-militaristic frame of mind.
Eventually, the situation becomes untenable, and the civilization collapses and is overrun. The invaders, still the less civilized of the two parties, are unable to correct the failures of the civilization, or even to maintain it in its decayed form.
Toynbee traces many instances of this pattern in excruciating detail, including the Roman Empire, Greece, and China. Mention is made also of the Soviet Union, Nazi Germany and France under Napoleon, as attempts at universal states. Unfortunately, Toynbee was not able to witness the collapse of the Soviet Union.
Sidebar: Toynbee's religious beliefs
Toynbee appears to be a Christian, but perhaps of a Modern sort. He says such things as the following (with all capitalization his),
"This mimesis of God can never expose human souls that devote themselves to it to those disillusionments that are apt to attend the mimesis of even the most godlike human beings The communion between the Soul and the One True God cannot thus degenerate into the bondage of a slave to a despot, for the Imitation of Christ [is] immune against the tragedy inherent in any mimesis that is directed towards unregenerate human personalities." [2, vol. 2, p. 108]
At the same time, he is clearly not a 2006 conservative Christian: "Religion must surrender to Science every province of intellectual knowledge to which Science can establish a title." [2, vol. 2, p. 381]
He clearly believes in man's sin nature and states that it plays a role in the undoing of a civilization. He does not see history as completely cyclical, as he recognizes that religion has gone through a linear transformation from pagan religions, to religions such as Christianity, finally to atheism.
America through Toynbee's Lens
One cannot read Toynbee's work and not speculate upon what he might have said, had he witnessed the events that came after his time. While I do not pretend to have his insight or knowledge of history, nor am I trying to put words in his mouth, the following is my analysis of where the United States stands today, attempting to use the same axes along which Toynbee has analyzed history.
America has been propelled by a powerful vision. Religious, civil and economic liberty--which channel human nature rather than attempting to deny or suppress it, as in failed systems--and a belief in a God who blesses those who seek Him, played a vital role in inspiring and motivating our forebears. And although Toynbee discounts the importance of an open frontier to a civilization, there should be no doubt that our readily available natural resources coupled with good old-fashioned materialism were also part of what allowed America to grow heartily.
Through much of our history, we have weathered challenges well. The Civil War, one of our greatest challenges, was resolved with an expanded vision that included the belief that human beings of all races are indeed created equal , a belief that spread to other areas such as suffrage. The Industrial Revolution followed, and our nation continued to grow.
However, the 20th century saw a number of challenges from which we have yet to recover, and which bring us closer to the specter of a universal state. All but one of these challenges came from within.
By the early part of the last century, our intellectual leaders were suffering infection from European humanism and religious skepticism, and were becoming enamoured with socialism and communism. FDR enlisted many of these people to help govern during the Great Depression. With power concentrated in this band of people whose ideas were dangerously out of touch with reality, America's economy was devastated , and its vision corrupted by the installation of the welfare state. Our nation's intellectual leaders have not genuinely solved a real problem since.
The United States met the challenge of World War II with military success, but our culture received a shock from which we have not recovered: With women forced to take on new roles and many young men absent, the family unit suffered and feminism lurched forward. The generation that sacrificed so much during the Depression and the War, had little left with which to fight cultural slippage after the War; hence the stage was set for the debacle of the 1960's.
Our intellectual leaders were undaunted by their failure to solve the Great Depression, but knocked senseless by the Second World War. By the 1950's and 60's, their ideas were more disconnected from reality than ever, yet their influence on our society was multiplied by the bestowment of the largest contingent of students to attend college in American history. Still enamoured with liberal ideas, intellectuals to this day busy themselves attempting to destroy Christianity, eroding our belief in the basic soundness of America's vision, and leaving no Founding Father, traditional hero or role model unmolested.
Therefore, much of our nation today is without any compelling vision for its own future. Much of the Christian church in America has lost its saltiness, and is useless for shining light on our path. This leaves the average American with a house swept clean, refilled with priorities such as avoiding boredom and seeking pleasure.As Toynbee predicted, the same visionless leaders (and their followers) are anti-military, arguing that if we want to stop terrorism, we should appease our enemies by shrinking back within our own (open) borders. While they argue for their naïve form of peace-through-surrender, they are proclaiming that they would not defend the nation if it were attacked again.
The Arab/Muslim cultures serve as today's barbarians. Their terrorist elements fit the definition of those who would destroy the dominant civilization, yet have nothing better to build in its place. They have the advantages Toynbee attributes to barbarians, including the ability to attack at the time and place of their choosing, to retreat easily when counterattacked (or just die on the spot), and to use our technology and wealth in the process. If we don't lose militarily, then, as is already happening in Europe , the barbarians may win by simply outbreeding us. 
From this it would be logical to conclude that we are near our universal state phase.
Fortunately, our nation is not a uniform collection of the visionless and culturally suicidal. A sizeable fraction still accepts the fact that there is a God, and believes in our nation's traditional vision. Many actively resist the establishment of a universal state. Patriotism is not dead; many are willing to fight to defend our country. However, to meet the severe challenges that our own leaders have handed us, we must do a number of things, starting with restoring America to a worship of the One True God, and thus restoring to ourselves a noble vision to motivate us to correct the other problems we face. If we return to Him, His help is assured.
 A search of the web will turn up mentions of there being 12 volumes in A Study of History, rather than 10. However, many of these references appear to be copied from each other. The second volume of my copy of the abridgement clearly states that it covers volumes 7 through 10 of the original work, and is the last volume of the abridgement. As further testimony to the inaccuracy of the World Wide Web, Toynbee's year of birth might be 1889 or 1899, and the year of his death 1974 or 1975.
 Toynbee, Arnold J., A Study of History, abridged by D. C. Somervell, Oxford University Press, 1957.
 Although most people are offended at the thought of not originating their own ideas, most evidently do copy the beliefs and behaviors of others, rather than finding their own. This phenomenon has been measured for instance, in preferences for music, where popular songs become more popular, although when judged apart from knowledge of the week's top 40, they are not found to be that good. Or consider the speed with which phrases from Saturday Night Live spread through our daily conversations, or the frequency with which the media's focal topic last night becomes the water cooler conversation the next morning--whether it merits such importance or not.
 We are still grappling with the issue of race today, but the expanded vision was articulated skillfully by Lincoln, and has been pursued ever since.
 Powell, Jim, FDR's Folly: How Roosevelt and His New Deal Prolonged the Great Depression. Crown Forum, 2003. ISBN: 0761501657.
 Even the rise of Islam in Europe can be traced back to World War II, and the Euro-Arab Dialogue.
 In a free society, any subculture that is unwilling to be assimilated into the larger culture and is willing to protest or riot, could qualify as a barbarian element in that society.